//
//  UIImage+Extention.m
//  Quote
//
//  Created by ihefe-003 on 15/6/11.
//  Copyright (c) 2015年 ihefe-003. All rights reserved.
//

#import "UIImage+Extention.h"

@implementation UIImage (Extention)
+(UIImage*)imageWithName:(NSString *)name{
    return [UIImage imageNamed:name];
}
+(UIImage *)resizeImage:(NSString *)name{
    UIImage *image=[UIImage imageWithName:name];
    return [image stretchableImageWithLeftCapWidth:image.size.width*0.5 topCapHeight:image.size.height*0.5];
}
/*  画出一张纯色的图片
 *
 *  @param color 图片的颜色
 *
 *  @return 返回一张纯色的图片
 */
+(UIImage*)imageWithColor:(UIColor *)color{
    CGFloat imageW=100;
    CGFloat imageH=100;
    //1.开启图形上下文
    UIGraphicsBeginImageContextWithOptions(CGSizeMake(imageW, imageH), NO, 0.0);
    //2.设置颜色
    [color set];
    //3.画一个color色的矩形框
    UIRectFill(CGRectMake(0, 0, imageW, imageH));
    //4.拿到图片
    UIImage *image=UIGraphicsGetImageFromCurrentImageContext();
    //5.关闭图形上下文
    UIGraphicsEndImageContext();
    return image;
}

+ (UIImage *)resizableImage:(NSString *)name{
    UIImage *normal = [UIImage imageNamed:name];
    CGFloat w = normal.size.width * 0.5;
    CGFloat h = normal.size.height * 0.5;
    return [normal resizableImageWithCapInsets:UIEdgeInsetsMake(h, w, h, w)];
}


/**
 *  获得某个像素的颜色
 *
 *  @param point 像素点的位置
 */
- (UIColor *)pixelColorAtLocation:(CGPoint)point {
    UIColor *color = nil;
    CGImageRef inImage = self.CGImage;
    CGContextRef contexRef = [self ARGBBitmapContextFromImage:inImage];
    if (contexRef == NULL) return nil;
    
    size_t w = CGImageGetWidth(inImage);
    size_t h = CGImageGetHeight(inImage);
    CGRect rect = {{0,0},{w,h}};
    
    // Draw the image to the bitmap context. Once we draw, the memory
    // allocated for the context for rendering will then contain the
    // raw image data in the specified color space.
    CGContextDrawImage(contexRef, rect, inImage);
    
    // Now we can get a pointer to the image data associated with the bitmap
    // context.
    unsigned char* data = CGBitmapContextGetData (contexRef);
    if (data != NULL) {
        //offset locates the pixel in the data from x,y.
        //4 for 4 bytes of data per pixel, w is width of one row of data.
        int offset = 4*((w*round(point.y))+round(point.x));
        int alpha =  data[offset];
        int red = data[offset+1];
        int green = data[offset+2];
        int blue = data[offset+3];
        //		NSLog(@"offset: %i colors: RGB A %i %i %i  %i",offset,red,green,blue,alpha);
        color = [UIColor colorWithRed:(red/255.0f) green:(green/255.0f) blue:(blue/255.0f) alpha:(alpha/255.0f)];
    }
    
    // When finished, release the context
    CGContextRelease(contexRef);
    // Free image data memory for the context
    if (data) { free(data); }
    
    return color;
}

/**
 *  根据CGImageRef来创建一个ARGBBitmapContext
 */
- (CGContextRef)ARGBBitmapContextFromImage:(CGImageRef) inImage {
    CGContextRef    context = NULL;
    CGColorSpaceRef colorSpace;
    void *          bitmapData;
    NSInteger             bitmapByteCount;
    NSInteger             bitmapBytesPerRow;
    
    // Get image width, height. We'll use the entire image.
    size_t pixelsWide = CGImageGetWidth(inImage);
    size_t pixelsHigh = CGImageGetHeight(inImage);
    
    // Declare the number of bytes per row. Each pixel in the bitmap in this
    // example is represented by 4 bytes; 8 bits each of red, green, blue, and
    // alpha.
    bitmapBytesPerRow   = (pixelsWide * 4);
    bitmapByteCount     = (bitmapBytesPerRow * pixelsHigh);
    
    // Use the generic RGB color space.
    //colorSpace = CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);  //deprecated
    colorSpace = CGColorSpaceCreateDeviceRGB();
    if (colorSpace == NULL)
    {
        fprintf(stderr, "Error allocating color space\n");
        return NULL;
    }
    
    // Allocate memory for image data. This is the destination in memory
    // where any drawing to the bitmap context will be rendered.
    bitmapData = malloc( bitmapByteCount );
    if (bitmapData == NULL)
    {
        fprintf (stderr, "Memory not allocated!");
        CGColorSpaceRelease( colorSpace );
        return NULL;
    }
    
    // Create the bitmap context. We want pre-multiplied ARGB, 8-bits
    // per component. Regardless of what the source image format is
    // (CMYK, Grayscale, and so on) it will be converted over to the format
    // specified here by CGBitmapContextCreate.
    context = CGBitmapContextCreate (bitmapData,
                                     pixelsWide,
                                     pixelsHigh,
                                     8,      // bits per component
                                     bitmapBytesPerRow,
                                     colorSpace,
                                     (CGBitmapInfo)kCGImageAlphaPremultipliedFirst);
    if (context == NULL)
    {
        free (bitmapData);
        fprintf (stderr, "Context not created!");
    }
    
    // Make sure and release colorspace before returning
    CGColorSpaceRelease( colorSpace );
    
    return context;
}
#pragma mark - 图片裁剪
+ (instancetype)imageWithName:(NSString *)name border:(CGFloat)border borderColor:(UIColor *)color
{
    // 圆环的宽度
    CGFloat borderW = border;
    
    // 加载旧的图片
    UIImage *oldImage =  [UIImage imageNamed:name];
    
    // 新的图片尺寸
    CGFloat imageW = oldImage.size.width + 2 * borderW;
    CGFloat imageH = oldImage.size.height + 2 * borderW;
    
    // 设置新的图片尺寸
    CGFloat circirW = imageW > imageH ? imageH : imageW;
    
    // 开启上下文
    UIGraphicsBeginImageContextWithOptions(CGSizeMake(circirW, circirW), NO, 0.0);
    
    // 画大圆
    UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(0, 0, circirW, circirW)];
    
    // 获取当前上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    
    // 添加到上下文
    CGContextAddPath(ctx, path.CGPath);
    
    // 设置颜色
    [color set];
    
    // 渲染
    CGContextFillPath(ctx);
    
    CGRect clipR = CGRectMake(borderW, borderW, oldImage.size.width, oldImage.size.height);
    
    // 画圆：正切于旧图片的圆
    UIBezierPath *clipPath = [UIBezierPath bezierPathWithOvalInRect:clipR];
    
    // 设置裁剪区域
    [clipPath addClip];
    
    
    // 画图片
    [oldImage drawAtPoint:CGPointMake(borderW, borderW)];
    
    // 获取新的图片
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    // 关闭上下文
    UIGraphicsEndImageContext();
    
    return newImage;
}
#pragma mark - 截屏
+ (instancetype)imageWithCaptureView:(UIView *)view
{
    // 开启上下文
    UIGraphicsBeginImageContextWithOptions(view.bounds.size, NO, 0.0);
    
    // 获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    
    // 渲染控制器view的图层到上下文
    // 图层只能用渲染不能用draw
    [view.layer renderInContext:ctx];
    
    // 获取截屏图片
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    // 关闭上下文
    UIGraphicsEndImageContext();
    
    return newImage;
}
@end
